U.S. patent application number 11/320928 was filed with the patent office on 2006-07-20 for hydrocracking catalysts for vacuum gas oil & de-metalized oil blend.
This patent application is currently assigned to Saudi Arabian Oil Company. Invention is credited to Shakeel Ahmed, Walid A. Al-Naeem.
Application Number | 20060157386 11/320928 |
Document ID | / |
Family ID | 36129933 |
Filed Date | 2006-07-20 |
United States Patent
Application |
20060157386 |
Kind Code |
A1 |
Al-Naeem; Walid A. ; et
al. |
July 20, 2006 |
Hydrocracking catalysts for vacuum gas oil & de-metalized oil
blend
Abstract
This invention relates to a catalyst and a process for treating
heavy hydrocarbons using the catalyst. The catalyst is useful for
treating heavy hydrocarbons, de-metallize oil (DMO) and is
particularly useful in VGO/DMO hydrocarbon blend. It is also useful
for DAO. The catalyst acts to catalytically convert the VGO/DMO
blend to shorter-chain valuable hydrocarbon products. The catalyst
includes a catalytic support material, a catalytic metal
impregnated upon the catalytic support material, and a promoter
metal on the catalytic support material to enhance catalytic
conversion. The combination of the catalytic support material with
catalytic metal and promoter metal is operable to catalytically
convert VGO/DMO into hydrocarbon products having shorter carbon
chains.
Inventors: |
Al-Naeem; Walid A.; (Damman,
SA) ; Ahmed; Shakeel; (Dhahran, SA) |
Correspondence
Address: |
BRACEWELL & GIULIANI LLP
P.O. BOX 61389
HOUSTON
TX
77208-1389
US
|
Assignee: |
Saudi Arabian Oil Company
|
Family ID: |
36129933 |
Appl. No.: |
11/320928 |
Filed: |
December 29, 2005 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60639909 |
Dec 29, 2004 |
|
|
|
Current U.S.
Class: |
208/120.01 |
Current CPC
Class: |
B01J 29/045 20130101;
B01J 29/166 20130101; B01J 23/85 20130101; B01J 35/002 20130101;
C10G 47/20 20130101; B01J 29/044 20130101; B01J 37/20 20130101;
B01J 35/1038 20130101; B01J 29/041 20130101; B01J 29/005 20130101;
C10G 45/12 20130101; B01J 2229/20 20130101; B01J 23/883 20130101;
B01J 29/7007 20130101; B01J 35/1019 20130101; B01J 29/0308
20130101; C10G 47/12 20130101; C10G 65/12 20130101; B01J 21/12
20130101; C10G 45/08 20130101; B01J 29/084 20130101; C10G 47/16
20130101 |
Class at
Publication: |
208/120.01 |
International
Class: |
C10G 11/04 20060101
C10G011/04 |
Claims
1. A catalyst for treating VGO/DMO hydrocarbon blend to
catalytically convert the VGO/DMO blend to shorter-chain valuable
hydrocarbon products, the catalyst comprising: a catalytic support
material comprising MCM-41 mesoporous material, a catalytic metal
impregnated upon the catalytic support material, and, a promoter
metal on the catalytic support material to enhance catalytic
conversion, the catalytic support material with catalytic metal and
promoter metal operable to catalytically convert VGO/DMO into
hydrocarbon products having shorter carbon chains.
2. The catalyst of claim 1 wherein the catalytic metal component is
molybdenum and the promoter metal is nickel.
3. The catalyst of claim 2 wherein the catalytic support material
is solely MCM-41 mesoporous material.
4. The catalyst of claim 2 wherein substantially all of the nickel
is in the form of nickel sulfide.
5. The catalyst of claim 1 wherein the catalytic metal component is
selected from the group consisting of molybdenum, tungsten and
combinations thereof, and wherein the promoter metal is selected
from a group consisting of nickel, cobalt and combinations
thereof.
6. The catalyst of claim 1 wherein the VGO/DMO hydrocarbon blend
contains at least 10% DMO by volume.
7. The catalyst of claim 1 wherein the VGO/DMO hydrocarbon blend
contains at least 15% DMO by volume.
8. The catalyst of claim 1 wherein the catalytic metal and the
promoter metal are impregnated upon the catalytic support through
co-impregnation.
9. The catalyst of claim 1 wherein the catalytic metal and the
promoter metal are impregnated upon the catalytic support through
successive impregnation.
10. The process of catalytically converting a heavy hydrocarbon
containing de-metallized oil comprising the steps of: introducing
the heavy hydrocarbon containing de-metallized oil into a reactor
stage, introducing the catalyst into the reactor stage, the
catalyst comprising: a catalytic support material comprising MCM-41
mesoporous material, a catalytic metal impregnated upon the
catalytic support material, and, a promoter metal on the catalytic
support material to enhance catalytic conversion, the catalytic
support material with catalytic metal and promoter metal operable
to catalytically convert at least a portion of the de-metallized
oil into hydrocarbon products having shorter carbon chains.
11. The process of claim 10 wherein the catalytic metal component
is molybdenum and the promoter metal is nickel.
12. The catalyst of claim 11 wherein the catalytic support material
includes ultra stable Y zeolite.
13. The process of claim 11 wherein the catalytic support material
is solely MCM-41 mesoporous material.
14. The process of claim 11 wherein the catalytic support material
includes .beta.-zeolite.
15. The process of claim 11 wherein the catalytic support material
includes amorphous silica alumina.
16. The process of claim 11 wherein the catalytic support material
is selected from the group consisting of ultra stable Y zeolite,
MCM-41 mesoporous material, .beta.-zeolite, amorphous silica
alumina, and combinations thereof.
17. The process of claim 11 wherein at least a portion of the
nickel is in the form of nickel sulfide.
18. The process of claim 11 wherein the catalytic metal component
is selected from the group consisting of nickel, cobalt and
combinations thereof, and wherein the promoter metal is selected
from a group consisting of molybdenum, tungsten and combinations
thereof.
19. The process of claim 11 wherein the VGO/DMO hydrocarbon blend
contains at least 10% DMO by volume.
20. The process of claim 11 wherein the VGO/DMO hydrocarbon blend
contains at least 15% DMO by volume.
21. The process of claim 18 wherein at least a portion of the
nickel is in the form of nickel sulfide.
22. The process of claim 18 wherein at least a portion of the
cobalt is in the form of cobalt sulfide.
23. The process of claim 10 wherein the catalytic metal and the
promoter metal are impregnated upon the catalytic support through
co-impregnation.
24. The process of claim 10 wherein the catalytic metal and the
promoter metal are impregnated upon the catalytic support through
successive impregnation.
25. The process of claim 10 further comprising the step of
maintaining a pre-defined temperature in the reactor.
26. The process of claim 25 wherein the pre-defined temperature is
at least 390 degrees C.
27. The process of claim 25 wherein the pre-defined temperature is
at least 400 degrees C.
Description
RELATED APPLICATIONS
[0001] This patent application claims priority to U.S. Provisional
Patent Application Ser. No. 60/639,909 filed on Dec. 29, 2004,
which is incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field of the Invention
[0003] This invention relates generally to the field of catalytic
treatment of heavy hydrocarbons to produce desirable hydrocarbon
products, in particular, a novel catalyst operable to catalytically
treat de-metallized oil (DMO) and Vacuum Gas Oil (VGO) Blend.
[0004] 2. Description of the Prior Art
[0005] The flexibility of hydrocracking as a process for refining
petroleum has resulted in its phenomenal growth during the past 15
years. Through catalytic treatment, feedstocks can be converted to
lower boiling or more desirable products. Hydrocarbon feedstocks
suitable for such treatment range from residue to naphtha. Products
include such widely diverse materials such as gasoline, kerosene,
middle distillates, lubricating oils, fuel oils, and various
chemicals.
[0006] Commercial hydrocracking is typically carried out in a
single stage reactor or in a two-stage reactor with the stages in
series. Numerous hydrocracking catalysts have been explored to
treat various hydrocarbons, to reduce undesirable side effects of
the catalytic treatment and/or to extend the life of the catalyst.
Development has also led to catalysts suitable for severe operating
conditions. Efforts for cost effectiveness are ongoing. The choice
of catalysts and of the particular process scheme will depend on
many factors such as feed properties, desired products properties,
size of the hydrocracking unit, and various other economic
considerations.
[0007] While hydrocracking has been investigated in the past for
the purpose of hydrocracking medium and heavy vacuum gas oil (VGO),
there is a need to address heavier and different hydrocarbons such
as de-asphalted oil (DAO) or de-metallized oil (DMO) to convert
this into suitable product for gasoline lines, jet fuels and diesel
oils according to geographical and seasonal variations in demand.
LPG and lubricating bases would also be desirable products. A
catalyst would be advantageous that is capable of handling large
hydrocarbon molecules and heavy poly-aromatic molecules, in
particular, DMO. A catalyst that can process VGO/DMO feed blend
would be particularly advantageous. As it is notable that the world
market is tending toward heavier hydrocarbons, a catalyst suitable
for such heavy hydrocarbons would be advantageous.
SUMMARY OF THE INVENTION
[0008] The current invention includes a catalyst for and a process
for hydrotreating/hydrocracking heavy hydrocarbons. The catalyst is
particularly useful for treating de-metallized oil (DMO) and is
particularly useful in VGO/DMO hydrocarbon blend. The catalyst acts
to catalytically convert the VGO/DMO blend to shorter-chain
valuable hydrocarbon products. The catalyst includes a catalytic
support material, a catalytic metal impregnated upon the catalytic
support material, and a promoter metal on the catalytic support
material to enhance catalytic conversion. The combination of the
catalytic support material with catalytic metal and promoter metal
is operable to catalytically convert VGO/DMO into hydrocarbon
products having shorter carbon chains.
[0009] In a preferred embodiment, the catalytic metal component
includes molybdenum and the promoter metal includes nickel.
[0010] Regarding the catalytic support materials, a particularly
preferred catalytic support material includes MCM-41 mesoporous
material. .gamma.-alumina was used as binder for all catalyst
prepared in this research. The amount of .gamma.-alumina used was
around 70% of the total catalyst support for the test runs. In a
particularly preferred embodiment, the USY zeolite is in an absence
of .gamma.-zeolite.
[0011] In another preferred embodiment, the catalytic support
material is .beta.-zeolite. In another preferred embodiment, the
catalytic support material is USY zeolite. In yet another preferred
embodiment, the catalytic support material is amorphous silica
alumina, also called ASA. ASA has a non-uniform structure with low
acidity and high surface area. The non-uniform structure tends to
create acidic sites that are not available to large molecules,
which leads to inferior performance of ASA alone as compared to
MCM-41 or a combination of MCM-41 with ASA. Similarly, the USY and
.beta.-zeolite supports suffer from drawbacks related to the
microporous nature of the supports which makes the catalyst less
efficient for large molecules since it is diffusion limited. These
supports used alone tend to plug rapidly, thereby deactivating the
catalyst. However, the MCM-41 support material overcomes these
flaws. In a preferred embodiment, the catalytic support material is
solely ultra stable Y zeolite, MCM41 mesoporous material,
.beta.-zeolite, amorphous silica alumina or combinations thereof. A
particularly preferred embodiment includes a single catalytic
support material that is substantially all MCM-41. This material is
mesoporous that is well-structured and has uniform morphology with
high surface area. It also has low acidity as compared to beta and
USY support materials. The invention includes the use of proper
support material and a balance between acidic and metallic function
with the proper distribution of metals throughout the support
material. This is accomplished through the very well-structured
morphology features of MCM-41 support material, which contains both
acidic and metallic site that are accessible to the large
hydrocarbon molecules found in VGO and DMO. For this reason, high
conversion is achieved. Advantageously the lower acidity of MCM-41
as compared to other support materials drives conversion toward
selectivity towards mid distillates and limits the production of
undesirable light gases.
[0012] In a preferred embodiment of the invention, the catalytic
metal is in a sulfide form. For example, molybdenum in the form of
molybdenum sulfide is preferred.
[0013] In a preferred embodiment, promoter metals include solely
nickel.
[0014] The catalyst of the invention is particularly useful for
VGO/DMO hydrocarbon blend contains at least 10% DMO by volume. Test
runs have been made for VGO/DMO hydrocarbon blend contains at least
15% DMO by volume.
[0015] Impregnation of the catalytic metal and the promoter metal
onto the catalytic support is accomplished through methods known in
the art, such as co-impregnation method. The process of
catalytically converting a heavy hydrocarbon containing
de-metallized oil includes the steps of introducing the heavy
hydrocarbon containing de-metallized oil into a reactor stage and
introducing the catalyst into the reactor stage. The catalyst
introduced into the reactor stage includes the catalytic support
material, the catalytic metal impregnated upon the catalytic
support material, and the promoter metal on the catalytic support
material to enhance catalytic conversion. The catalytic support
material with catalytic metal and promoter metal operate to
catalytically convert at least a portion of the de-metallized oil
into hydrocarbon products having shorter carbon chains.
[0016] The process reaches and maintains a pre-defined temperature
in the reactor operable to achieve conversion. In a preferred
embodiment, the pre-defined temperature is at least 390 degrees C.
In a more particularly preferred embodiment, the pre-defined
temperature is at least 400 degrees C.
[0017] In a preferred embodiment, a majority of the pores of the
catalyst support are located within 20 to 50 Angstrom (.ANG.) and
the catalyst support has a large surface area as measured through
pore size distribution. Table 1 shows examples of preferred
embodiments. TABLE-US-00001 TABLE 1 Prepared Catalysts Textual
Characteristics Average BET Surface Area Pore Volume Pore Diameter
Sample (m.sup.2/g) (cm.sup.3/g) (A.sup.0) NiMo-ASA 186 0.33 36
NiMo-MCM-41 324 0.40 25 NiMo-.beta. 313 0.41 26 NiMo-USY 300 0.35
23
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] So that the manner in which the features, advantages and
objects of the invention, as well as others that will become
apparent, may be understood in more detail, more particular
description of the invention briefly summarized above may be had by
reference to the embodiment thereof which is illustrated in the
appended drawings, which form a part of this specification. It is
to be noted, however, that the drawings illustrate only a preferred
embodiment of the invention and is therefore not to be considered
limiting of the invention's scope as it may admit to other equally
effective embodiments.
[0019] FIG. 1 depicts a schematic of a preferred embodiment of the
process with the catalyst of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Several catalysts were prepared using nickel (Ni)/molybdenum
(Mo) metals loadings along with the four different support
materials identified above. The four catalyst formulations created
in this manner were characterized using gas sorption analyzer,
temperature programmed reduction (TPR) and temperature programmed
de-sorption (TPD). Moreover, the catalyst formulations were tested
in a batch reactor and compared against a commercial catalyst. The
outcome of this work showed that the formulation including MCM-41
catalyst support, resulting in NiMo-MCM-41, has performed better
than the commercial catalyst on heavy hydrocarbons, in particular,
VGO/DMO blends. NiMo-MCM-41 showed higher hydrodesulfurization
(HDS) and hydrogenation activities. In addition, it had higher
conversion and higher diesel yield than commercial catalyst.
[0021] Most of the hydrocracking catalysts of commercial interest
are dual functional in nature, consisting of both a
hydrogenation-dehydrogenation component and an acidic support. The
reactions catalyzed by the individual components are quite
different. In specific catalysts, the relative strengths of the two
components can be varied. The reactions occurring and the products
formed are influenced by the balance between these two components.
TABLE-US-00002 TABLE 2 Acidity for all prepared catalysts Catalyst
Acidity (mmol/g) Peak Temperature (.degree. C.) NiMo-MCM-41 0.33
264 NiMo-ASA 0.50 252 NiMo-.beta. 0.56 233 NiMo-USY 0.59 238
[0022] Table 2 shows the TPD of ammonia for all of the prepared
hydrocracking catalysts. The acidity of the prepared catalysts
ranges from 0.33 mmol/g (NiMo-MCM-41) to 0.59 mmol/g (NiMo-USY).
The lower acidity of NiMo-MCM-41 catalyst is expected since MCM-41
is a silica based material and has low amount of alumina.
Therefore, NiMo-MCM-41 catalyst has lower amount of .gamma.-alumina
than the other prepared catalysts.
[0023] The catalytic metal, such as molybdenum, and the promoter
metal, such as nickel, provide the hydrogenation-dehydrogenation
functions. As noted, this is preferably in the sulfide form. Other
group VIA and group VIIIA metals are useful as promoter metal and
catalytic metal. These metals catalyze the hydrogenation of the
feedstock, making it more reactive for cracking and heteroatom
removal, as well as reducing the coking rate. They also initiate
the cracking by forming a reactive olefin intermediate via
dehydrogenation.
[0024] Since hydrocracking of industrial feedstocks is to be
carried in presence of hydrogen sulfide and organic sulfur
compounds, it is preferred that the metal site be in a metal
sulfide form of the VIA group promoted by a nickel or cobalt
sulfide.
[0025] The reactions that occur during the hydrocracking process
take three major routes. First, non-catalytic thermal cleavage of
C-C bonds via hydrocarbon radicals, with hydrogen addition
(hydropyrolysis). Second, monofunctional C-C bond cleavage with
hydrogen addition over hydrogenation components consisting of
metals, oxides or sulfides (hydrogenolysis). Third, bifunctional
C-C bond cleavage with hydrogen addition over bifunctional
catalysts consisting of a hydrogenation component dispersed on a
porous, acidic support. In addition to the above reactions, there
are other reactions that take place during the hydrocracking
process. These can include hydrodesulfurization,
hydrodeintrofication, hydrodeoxigenation, olefin hydrogenation and
partial aromatic hydrogenation. TABLE-US-00003 TABLE 3 Experimental
Design Catalyst Systems Com- NiMo- NiMo- NiMo- NiMo- mercial MCM-41
USY .beta. ASA Catalyst Preparation .gamma.-alumina binder, 70 70
70 70 wt % Support, wt % 30 30 30 30 NiO, wt % 2.5 2.5 2.5 2.5
MoO3, wt % 12 12 12 12 Ni, wt % 2 2 2 2 Mo, wt % 8 8 8 8 Atomic
Ratio 0.2 0.2 0.2 0.2 Catalyst Characterization Surface Area, 324
300 313 186 m.sup.2/g Pore Vol., cm.sup.3/g 0.4 0.35 0.41 0.33 Pore
Size, 25 23 26 36 Angstrom Acidity, 0.33 0.59 0.56 0.5 mmol/gm
Catalyst Evaluation Batch Reactor -- -- No. of Runs 5 1 1 1 1
Temperatures, 410 410 410 410 410 deg. C. Pressures, kg/cm.sup.2
150 150 150 150 150 Feed weight, g 100 100 100 100 100 Catalyst
weight, g 3 3 3 3 3
[0026] The commercial catalyst that was used for comparison is
DHC-8 from Universal Oil Products (UOP) Company. .gamma.-alumina
was used as binder for all catalyst prepared in this test shown
above. The amount of .gamma.-alumina used was 70% of the total
catalyst support. TABLE-US-00004 TABLE 4 Feedstock Definition
VGO/DMO Feedstock Properties VGO DMO 85%/15% Specific Gravity
0.92-0.93 0.96-0.97 0.93-0.94 Total Nitrogen, wt ppm 700-900
1300-2100 1100-1200 Total Sulfur, wt % 2-3 3-3.5 2.6-2.8 ASTM
Distillation, D2887 5%, .degree. C. 279 402 50%, max .degree. C.
472 596 495 90%, max .degree. C. 543 678 615 Ni + V wt. ppm <1
8.0-13.5 2-3
[0027] TABLE-US-00005 TABLE 5 Tested catalysts conversion for
800-900.degree. F. cut and 900-1050.degree. F. cut .sup.1Conversion
% NiMo- NiMo- NiMo- NiMo- Cut Range, .degree. F. Commercial MCM-41
.beta. ASA USY 800-900 13.37 19.23 17.57 15.78 15.04 900-1050 35.29
36.33 32.74 34.56 35.69 Overall 27.01 29.97 27.01 27.47 27.89
[0028] Among the four catalyst formulations described above that
are encompassed within the invention, NiMo-MCM-41 catalyst had the
lowest acidity and the highest surface area. This is attributed to
the fact that MCM-41 is a silica-based material and has low amounts
of alumina. This is one of the advantages of MCM-41 being
mesoporous and having low acidity. The mesoporous feature along
with the lower acidity of NiMo-MCM41 catalyst promotes the highest
conversion and the lowest gas make.
[0029] While the invention has been shown or described in only some
of its forms, it should be apparent to those skilled in the art
that it is not so limited, but is susceptible to various changes
without departing from the scope of the invention.
* * * * *